CN215342741U

CN215342741U - Cover plate device for lithium battery

Info

Publication number: CN215342741U
Application number: CN202121544997.9U
Authority: CN
Inventors: 陈玉升; 艾建忠
Original assignee: Suzhou Sumzone New Energy Technology Co ltd
Current assignee: Suzhou Sumzone New Energy Technology Co ltd
Priority date: 2021-07-08
Filing date: 2021-07-08
Publication date: 2021-12-28
Anticipated expiration: 2031-07-08

Abstract

The utility model provides a apron device for lithium cell, includes the apron body, has insulating backing plate on the surface of the next side of orientation of apron body, and there is positive plate, right-hand member top to have the negative plate, characteristics above the left end of apron body: there is anodal connecting piece at insulating backing plate one side surface under the orientation, the negative pole connecting piece, anodal connecting piece includes anodal bed plate, it is close to the tip both sides of apron body left end and has a pair of anodal pin downwards, the negative pole connecting piece includes the negative pole bed plate, it is close to the tip of apron body right-hand member and has a pair of negative pole pin downwards, anodal connecting piece, insulating backing plate, realize fixedly through anodal rivet between apron body and the positive plate, the negative pole connecting piece, insulating backing plate, realize fixedly through negative pole rivet between apron body and the negative plate, just, the upside of the rivet cap of negative pole rivet all is formed with a profile of tooth on the surface. Simple structure, reduce the internal resistance, prevent that the lithium-ion core from producing and rocking, guarantee fastness and electrical connection effect, improve bearing capacity.

Description

Cover plate device for lithium battery

Technical Field

The utility model belongs to the technical field of lithium battery components, and particularly relates to a cover plate device for a lithium battery.

Background

Lithium ion power batteries have the advantages of high energy density, light weight, high capacity, long cycle life, safety, reliability and the like, and at present, lithium batteries are widely applied to products such as new energy automobiles, energy storage equipment, electric hardware tools and the like. As is known in the art, a lithium battery is composed of a case, a lithium battery cell, which may be referred to as a winding core, disposed in the case, and includes a positive plate, a separator, and a negative plate, wherein the separator separates the positive plate from the negative plate, and has a positive plate foil and a negative plate foil extending portion on two sides of the lithium battery cell, and a cover plate disposed on the upper portion of the lithium battery cell and welded and sealed therewith to form the battery. The cover plate is the main part of the lithium battery and comprises a cover plate base body, positive and negative poles, a sealing gasket, an electrode pressing plate, an electrode lead piece and the like. The prior chinese patent documents do not contain any relevant technical information about lithium battery covers, and include CN209045625U (a cover plate for automotive power lithium battery), CN208521985U (a top cover plate assembly for power battery), CN207082566U (a cover plate for lithium battery), CN107452904A (a top cover plate for liquid leakage prevention and overcharge prevention lithium battery and its application), CN203871392U (integrated high riveting type cover plate for lithium battery), and so on.

Typically, a square aluminum shell lithium battery and a battery cover plate thereof are introduced as the Chinese patent application publication No. CN111785864A, which discloses a battery cover plate, wherein a positive electrode rivet sequentially penetrates through a sealing ring, a supporting frame, a base plate, a rotation stopping sheet and a positive electrode pressing plate to be riveted, a negative electrode rivet sequentially penetrates through the sealing ring, the supporting frame, the base plate, a negative electrode insulation plate and a negative electrode pressing plate to be riveted, a positive electrode adapter sheet is welded under the positive electrode rivet, a negative electrode adapter sheet is welded under the negative electrode rivet, the center of the base plate is provided with an explosion-proof hole, an explosion-proof sheet is arranged in the explosion-proof hole, the top of the explosion-proof hole is provided with an explosion-proof film, the base plate is provided with a liquid injection hole, the liquid filling hole is internally and hermetically provided with a sealing nail and a sealing sheet, the two ends of the base plate are also provided with cylindrical positioning columns, the rotation stopping sheet and the negative electrode insulation plate are provided with positioning holes which are connected with the positioning columns in an embedded mode, and the technical scheme can guarantee the overall safety and stability of the square aluminum shell lithium battery. However, the technical scheme still has the following problems: firstly, the anode adapter plate is welded below the anode rivet, the cathode adapter plate is welded below the cathode rivet, riveting operation is needed after the anode rivet and the cathode rivet are riveted with the upper substrate, the anode pressing plate and the cathode pressing plate in the production and manufacturing process, the whole structure is complex, the number of parts is large, the production cost is undoubtedly greatly increased, and the follow-up maintenance is not facilitated; secondly, not being limited to the current cover plate structure introduced in this technical document is mostly provided with the flaky positive pole lead piece and the negative pole lead piece, and the positive pole lead piece and the negative pole lead piece are electrically connected with the lithium battery cell, but the flaky lead piece is easily twisted, and will deform under the condition of small stress, which obviously affects the stability of the cover plate structure and the overall safety and stability of the temporal part of the lithium battery.

In view of the above-mentioned prior art, there is a need for a reasonable improvement of the cover plate device of the existing lithium battery. The applicant has therefore made an advantageous design, in the context of which the solution to be described below is made.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide a cover plate device for a lithium battery, which is simple in structure, reliable and safe, is beneficial to ensuring the combination firmness of a positive plate and a negative plate and a positive connecting piece and a negative connecting piece while simplifying the structure, ensuring the electrical connection effect between the positive plate and the negative connecting piece, reducing the production cost, and being beneficial to improving the bearing capacity and ensuring the connection stability by adopting a pin structure and a lithium battery core to realize electrical connection by abandoning the original flaky lead structure.

The utility model aims to solve the problem that the cover plate device for the lithium battery comprises a cover plate body, wherein an insulating base plate is positioned and installed on the downward side surface of the cover plate body, a positive plate is installed above the end part, close to the left end, of the cover plate body in an insulating mode, a negative plate is installed above the end part, close to the right end, of the cover plate body in an insulating mode, a positive connecting piece is positioned and installed on the downward side surface of the insulating base plate and at the position corresponding to the lower position of the positive plate, a negative connecting piece is positioned and installed on the downward side surface of the insulating base plate and at the position corresponding to the lower position of the negative plate, the positive connecting piece and the negative connecting piece are identical in structure and are symmetrically arranged, the positive connecting piece comprises a positive base plate, and a pair of positive pin pins are formed on the two sides of the end part, close to the left end, of the cover plate body, of the positive base plate and downward pins The negative pole connecting piece is including a negative pole bed plate, is close to in this negative pole bed plate be formed with a pair of negative pole pin under the tip orientation of apron body right-hand member, and is a pair of anodal pin is lath structure and extends the setting along vertical direction and realize electric connection with the lithium cell, realize through at least one anodal rivet between anodal connecting piece, insulating backing plate, the apron body and the positive plate and be connected fixedly and realize electric conduction between anodal connecting piece and the positive plate, and on the same way, realize through at least one negative pole rivet between negative pole connecting piece, insulating backing plate, the apron body and the negative plate and be connected fixedly and realize electric conduction between negative pole connecting piece and the negative plate, just the upside of the rivet cap of anodal rivet and negative pole rivet all is formed with a profile of tooth face on the surface.

In a specific embodiment of the utility model, a pressure relief explosion-proof hole penetrating through the thickness direction of the cover plate body is formed in the middle position of the cover plate body in the length direction, a pressure relief explosion-proof mechanism is arranged on the pressure relief explosion-proof hole and at a position corresponding to one side of the cover plate body, which is opposite to the insulating base plate in the use state, an explosion-proof mechanism installation cavity is formed on the cover plate body and around the circumference direction of the pressure relief explosion-proof hole, and the pressure relief explosion-proof mechanism is connected and fixed with the explosion-proof mechanism installation cavity in a state corresponding to the pressure relief explosion-proof hole.

In another specific embodiment of the present invention, the pressure relief explosion-proof mechanism includes an explosion-proof plate and a protective film, wherein an explosion-proof plate pressure-bearing cavity is formed at a central position of the explosion-proof plate, the explosion-proof plate pressure-bearing cavity is of a hemispherical structure and is disposed at an upper position corresponding to the pressure relief explosion-proof hole, a peripheral edge portion of the explosion-proof plate is welded to a cavity bottom wall of the explosion-proof mechanism mounting cavity, the protective film is disposed at an upper position corresponding to the explosion-proof plate, and a lower surface of the protective film is attached to an upper side surface of the cover plate body.

In another embodiment of the present invention, the explosion-proof sheet is made of aluminum foil, and the protective film is made of plastic and is transparent.

In still another embodiment of the present invention, a positive electrode plate insulating sleeve is fixed to the cap body at a position near the left end of the upper surface thereof and corresponding to a position below the positive electrode plate by injection molding, and similarly, a negative electrode plate insulating sleeve is fixed to the cap body at a position near the right end of the upper surface thereof and corresponding to a position below the negative electrode plate by injection molding.

In a further specific embodiment of the present invention, a liquid injection hole is formed in the cover plate body at a position corresponding to a position between the pressure relief explosion-proof hole and the positive electrode plate, the liquid injection hole penetrates through the thickness direction of the cover plate body and can be used for injecting an electrolyte into a shell cavity of a lithium battery shell, and a liquid injection abdication hole is formed in the insulating base plate at a position corresponding to the liquid injection hole.

In a further specific embodiment of the present invention, the insulating pad and the cover body are attached to each other on the surface facing the lower side, a positioning protection box is formed at the middle position in the length direction of the insulating pad, a plurality of explosion-proof vent holes are formed in the bottom plate of the positioning protection box and at the lower position corresponding to the pressure relief explosion-proof holes, a plurality of explosion-proof vent holes are formed in the side plates on the periphery of the positioning protection box, pin positioning plates are respectively formed at the two ends in the length direction of the insulating pad, and the two pin positioning plates respectively position the positive pin and the negative pin.

In a further specific embodiment of the present invention, the positive plate is provided with at least one positive plate riveting hole penetrating through the thickness direction of the positive plate, the positive base plate of the positive connecting member is also provided with a positive base plate riveting hole at a position corresponding to the positive plate riveting hole, the cover plate body, the insulating pad plate and the positive plate insulating sleeve are also provided with a riveting hole corresponding to the positive plate riveting hole, and the positive rivet sequentially penetrates through the corresponding positive base plate riveting hole, the insulating pad plate, the cover plate body, the positive plate insulating sleeve and the positive plate riveting hole from top to bottom, and then the positive connecting member and the positive plate are connected and riveted together to realize an electrical conduction relationship; similarly, the negative plate is provided with at least one negative plate riveting hole penetrating through the thickness direction of the negative plate, the negative plate riveting hole is also formed in the position, corresponding to the negative plate riveting hole, of the negative base plate of the negative connecting piece, the riveting hole is also formed in the positions, corresponding to the negative plate riveting hole, of the cover plate body, the insulating base plate and the negative plate insulating sleeve, the negative rivet sequentially penetrates through the corresponding negative base plate riveting hole, the insulating base plate, the cover plate body, the negative plate insulating sleeve and the negative plate riveting hole from top to bottom, and then the negative connecting piece and the negative plate are connected and riveted together to realize the electrical conduction relationship.

In yet another specific embodiment of the present invention, the cover plate body is made of an aluminum plate, and the insulating pad, the positive plate insulating sleeve and the negative plate insulating sleeve are made of teflon.

In a further specific embodiment of the present invention, the positive connector and the negative connector are of an integral structure, and the indented surfaces of the upper side surfaces of the rivet caps of the positive rivet and the negative rivet are of grid-shaped rack structure surfaces.

According to the technical scheme provided by the utility model, as the positive rivet and the negative rivet are riveted to form an integrated structure, the positioning stability of the positive connecting piece and the negative connecting piece and the combination firmness of the positive connecting piece and the negative connecting piece with the positive plate and the negative plate are effectively ensured, so that the electric conduction effect between the positive connecting piece and the negative connecting piece is ensured, and meanwhile, the tooth-grained surface on the rivet cap can ensure that the positive rivet and the positive connecting piece and the negative rivet are firmly combined with each other, so that the internal resistance of the electrical connection between the cover plate device and the lithium battery core can be reduced, the overcurrent multiplying power of the battery is improved, the integral structure is greatly simplified, the production cost is reduced, and the subsequent maintenance is facilitated; secondly, compared with a sheet-shaped lead piece structure, the bearing capacity of the cover plate device is greatly improved through the upright positive pin and the upright negative pin, the cover plate device cannot be easily deformed, and the positive pin and the positive connecting seat, and the negative pin and the negative connecting seat are integrated, so that the torsional strength of the positive connecting piece and the negative connecting piece can be further enhanced, the stability and the reliability of the electrical connection between the cover plate device and the lithium battery cell are greatly improved, and the over-current multiplying power of the battery can be effectively improved; thirdly, because the insulating base plate is arranged below the cover plate body, the reliability of electrical isolation and insulation between the anode connecting piece and the cover plate body and between the cathode connecting piece and the cover plate body can be effectively ensured, and the short circuit situation can not occur, meanwhile, a positioning protection box and an explosion-proof vent hole are additionally arranged, the bottom plate of the positioning protection box is propped against the lithium battery core, the lithium battery core can be firmly arranged in the shell, can not shake around under the interference of some external force, can not scratch components such as the cover plate body and the like, ensures the normal use of the lithium battery core and prolongs the service life of the lithium battery core, in addition, once the electrolyte leaks or even explodes and other serious accidents happen to the lithium battery core, the electrolyte can flow out of the explosion-proof vent holes to avoid flowing around, meanwhile, pressure gas in the lithium battery core can be orderly discharged from the holes so as to prevent the pressure gas from overflowing; fourthly, because the material of the protection film of the pressure relief explosion-proof mechanism is plastic and is in a transparent state, the problems of breakage, burst, breakage and the like of the explosion-proof sheet can be clearly and visually found, so that the detection and maintenance measures can be rapidly taken for the whole lithium battery.

Drawings

FIG. 1 is an overall structure diagram of an embodiment of the present invention

Fig. 2 is an exploded view of the embodiment of fig. 1.

In the figure: 1. the cover plate comprises a cover plate body, 11 pressure-relief explosion-proof holes, 111 explosion-proof mechanism mounting cavities, 12 pressure-relief explosion-proof mechanisms, 121 explosion-proof sheets, 1211 explosion-proof sheet pressure-bearing cavities, 122 protective films and 13 liquid injection holes; 2. the anti-explosion protection device comprises an insulating base plate, 21 liquid injection yielding holes, 22 positioning protection boxes, 221 anti-explosion vent holes, 222 anti-explosion vent holes and 23 pin positioning plates; 3. the positive plate comprises a positive plate, a positive plate insulating sleeve 31, a positive plate riveting hole 32; 4. a negative plate, 41, a negative plate insulating sleeve and 42, a negative plate riveting hole; 5. the positive electrode base plate is provided with a positive electrode connecting piece, 51 positive electrode base plates, 511 positive electrode base plate riveting holes and 52 positive electrode pins; 6. the negative electrode comprises a negative electrode connecting piece, 61 negative electrode base plates, 611 negative electrode plate base riveting holes and 62 negative electrode pins; 7. a positive rivet; 8. and a negative rivet.

Detailed Description

The following detailed description of the embodiments of the present invention will be described with reference to the accompanying drawings, but the description of the embodiments by the applicant is not intended to limit the technical solutions, and any changes made in the form of the present invention rather than the essential changes should be regarded as the protection scope of the present invention.

In the following description, all the concepts related to the directions or orientations of up, down, left, right, front and rear are based on the position shown in fig. 1, and thus, should not be interpreted as a particular limitation to the technical solution provided by the present invention.

Referring to fig. 1 and 2, the present invention relates to a cover plate device for a lithium battery, including a cover plate body 1, wherein the cover plate body 1 is in a long plate shape; an insulating pad 2 is positioned and mounted on the downward-facing side surface of the cap body 1, a positive electrode plate 3 is mounted on the cap body 1 in an insulating manner at a position above the end portion near the left end, and a negative electrode plate 4 is mounted on the cap body 1 in an insulating manner above the end portion near the right end.

The technical key points of the technical scheme provided by the utility model are as follows: a positive electrode connecting member 5 is positioned and mounted on the surface of the insulating base plate 2 facing downward and at a position corresponding to the lower portion of the positive electrode plate 3, a negative electrode connecting member 6 is positioned and mounted on the surface of the insulating base plate 2 facing downward and at a position corresponding to the lower portion of the negative electrode plate 4, the positive electrode connecting member 5 and the negative electrode connecting member 6 have the same structure and are symmetrically arranged, the positive electrode connecting member 5 includes a positive electrode base plate 51, a pair of positive electrode pins 52 are formed on the positive electrode base plate 51 facing downward at both sides of the end portion close to the left end of the cover plate body 1, the negative electrode connecting member 6 also includes a negative electrode base plate 61, a pair of negative electrode pins 62 are formed on the negative electrode base plate 61 facing downward at the end portion close to the right end of the cover plate body 1, the pair of positive electrode pins 52 and the pair of negative electrode pins 62 are both of a plate-like structure and extend in the vertical direction and are electrically connected to the lithium battery cell The aforesaid positive connecting piece 5, insulating backing plate 2, realize between apron body 1 and the positive plate 3 through at least one anodal rivet 7 that the connection is fixed and realize electric conduction between positive connecting piece 5 and the positive plate 3, likewise, aforesaid negative pole connecting piece 6, insulating backing plate 2, realize between apron body 1 and the negative plate 4 through at least one negative pole rivet 8 that the connection is fixed and realize electric conduction between negative pole connecting piece 6 and the negative plate 4, and all be formed with a profile of tooth face on the upside surface of the rivet cap of aforesaid anodal rivet 7 and negative pole rivet 8. As shown in fig. 1 and 2, the number of the positive rivets 7 and the number of the negative rivets 8 are two, but the number thereof is not limited thereto and can be changed accordingly.

In this embodiment, a pressure relief explosion-proof hole 11 penetrating through the thickness direction of the cover plate body 1 is formed in the middle of the cover plate body 1 in the length direction, a pressure relief explosion-proof mechanism 12 is disposed on the pressure relief explosion-proof hole 11 and at a position corresponding to a side of the cover plate body 1 facing away from the insulating pad 2 in the use state, an explosion-proof mechanism installation cavity 111 is formed on the cover plate body 1 and around the circumferential direction of the pressure relief explosion-proof hole 11, and the pressure relief explosion-proof mechanism 12 is connected and fixed with the explosion-proof mechanism installation cavity 111 in a state corresponding to the pressure relief explosion-proof hole 11.

Further, the pressure relief explosion-proof mechanism 12 includes an explosion-proof plate 121 and a protection film 122, wherein an explosion-proof plate pressure-bearing cavity 1211 is formed at a central position of the explosion-proof plate 121, the explosion-proof plate pressure-bearing cavity 1211 is of a hemispherical structure and is disposed at a position corresponding to an upper position of the pressure relief explosion-proof hole 11, a peripheral edge portion of the explosion-proof plate 121 is welded to a cavity bottom wall of the explosion-proof mechanism mounting cavity 111, the protection film 122 is disposed at a position corresponding to an upper position of the explosion-proof plate 121, and a lower surface of the protection film 122 is attached to an upper surface of the cover plate body 1.

Preferably, the explosion-proof sheet 121 is made of aluminum foil, and the protective film 122 is made of plastic and is transparent.

With continued reference to fig. 1 and 2, a positive plate insulating sleeve 31 is fixed to the cap body 1 at a position near the left end of the upper surface and corresponding to a position below the positive plate 3 by injection molding, and a negative plate insulating pad 41 is fixed to the cap body 1 at a position near the right end of the upper surface and corresponding to a position below the negative plate 4 by injection molding.

Furthermore, a liquid injection hole 13 is formed in the cover plate body 1 at a position corresponding to a position between the pressure relief explosion-proof hole 11 and the positive electrode plate 3, the liquid injection hole 13 penetrates through the thickness direction of the cover plate body 1, and the liquid injection hole 13 can be used for injecting an electrolyte into a case cavity of a lithium battery case.

Furthermore, the insulating base plate 2 and the cover plate body 1 are attached to the surface facing the next side, a positioning protection box 22 is formed in the middle of the insulating base plate 2 in the length direction, and a bottom plate of the positioning protection box 22 is abutted against the lithium battery cell downwards, so that the lithium battery cell is prevented from shaking under the interference of external force, and the mounting firmness of the lithium battery cell is guaranteed; a plurality of explosion-proof vent holes 221 are formed in the bottom plate of the positioning protection box 22 and at positions corresponding to the positions below the pressure relief explosion-proof holes 11, a plurality of explosion-proof air outlets 222 are formed in the side plates around the positioning protection box 22, a pin positioning plate 23 is formed at each end of the insulating base plate 2 in the length direction, and the two pin positioning plates 23 are used for positioning the positive pin 52 and the negative pin 62 respectively; once the pressure in the lithium battery shell exceeds the preset value, the explosion-proof sheet 121 bursts and breaks under the action of the pressure, the pressure gas in the aluminum battery shell is discharged through the explosion-proof vent hole 221, the explosion-proof vent hole 222 and the pressure-releasing explosion-proof hole 11, the burst explosion-proof sheet 121 is buffered by the protective film 122, the secondary damage caused by sputtering on an adjacent lithium battery, such as electrical short circuit, is avoided, and because the protective film 122 is in a transparent state, once the explosion-proof sheet 121 is damaged or burst and breaks and other problems, the problems can be clearly and intuitively found, so that the detection and maintenance measures can be quickly taken on the whole lithium battery.

In the present embodiment, at least one positive plate riveting hole 32 penetrating through the positive plate 3 in the thickness direction of the positive plate is formed, a positive base plate riveting hole 511 is also formed in the positive base plate 51 of the positive connector 5 at a position corresponding to the positive plate riveting hole 32, riveting holes are also formed in the cap body 1, the insulating base plate 2, and the positive plate insulating sleeve 31 corresponding to the positive plate riveting hole 32, and the positive rivet 7 passes through the corresponding positive base plate riveting hole 511, the insulating base plate 2, the cap body 1, the positive plate insulating sleeve 31, and the positive plate riveting hole 32 in this order from top to bottom, and then the positive connector 5 and the positive plate 3 are connected and riveted together to achieve an electrical connection; similarly, the negative electrode plate 4 is provided with at least one negative electrode plate rivet hole 42 penetrating through the thickness direction of the negative electrode plate 4, the negative electrode base plate rivet hole 611 is also provided in the position corresponding to the negative electrode plate rivet hole 42 in the negative electrode base plate 61 of the negative electrode connecting member 6, the rivet hole is also provided in the position corresponding to the negative electrode plate rivet hole 42 in the cover plate body 1, the insulating base plate 2, and the negative electrode plate insulating sleeve 41, and the negative electrode rivet 8 passes through the corresponding negative electrode base plate rivet hole 611, the insulating base plate 2, the cover plate body 1, the negative electrode plate insulating sleeve 41, and the negative electrode plate rivet hole 42 in this order from top to bottom, and then the negative electrode connecting member 6 and the negative electrode plate 4 are connected and riveted together to achieve an electrical connection.

Preferably, the cover plate body 1 is made of an aluminum plate, and the insulating pad 2, the positive plate insulating sleeve 31 and the negative plate insulating sleeve 41 are made of polytetrafluoroethylene; the positive connecting piece 5 and the negative connecting piece 6 are of an integrated structure, and the insection surfaces of the upper side surfaces of the rivet caps of the positive rivet 7 and the negative rivet 8 are of grid-shaped rack structure surfaces.

In conclusion, the technical scheme provided by the utility model overcomes the defects in the prior art, successfully completes the utility model task and truly realizes the technical effects of the applicant in the technical effect column.

Claims

1. The utility model provides a apron device for lithium cell, is including a apron body (1), and on the orientation next side surface of this apron body (1) fixed a position install an insulating backing plate (2), and the top position department of nearly left end tip of apron body (1) installs a positive plate (3) in insulation, and then installs a negative plate (4) in the top of the nearly right end tip of this apron body (1) in insulation, its characterized in that: a positive connecting piece (5) is positioned and installed on the surface of the insulating base plate (2) facing downwards and at a position corresponding to the lower part of the positive plate (3), a negative connecting piece (6) is positioned and installed on the surface of the insulating base plate (2) facing downwards and at a position corresponding to the lower part of the negative plate (4), the positive connecting piece (5) and the negative connecting piece (6) are the same in structure and are symmetrically arranged, the positive connecting piece (5) comprises a positive base plate (51), a pair of positive pins (52) are formed downwards on two sides of the end part of the positive base plate (51) close to the left end of the cover plate body (1), the negative connecting piece (6) comprises a negative base plate (61), a pair of negative pins (62) are formed downwards on the end part of the negative base plate (61) close to the right end of the cover plate body (1), it is a pair of anodal pin (52) and a pair of negative pole pin (62) are the lath structure and extend the setting and realize electric connection with the lithium cell along vertical direction, realize through at least one anodal rivet (7) between anodal connecting piece (5), insulating backing plate (2), apron body (1) and positive plate (3) that to connect fixedly and realize electric conduction between anodal connecting piece (5) and positive plate (3), likewise, realize through at least one negative pole rivet (8) between negative connecting piece (6), insulating backing plate (2), apron body (1) and negative plate (4) and connect fixedly and realize electric conduction between negative connecting piece (6) and negative plate (4), just all be formed with a profile of tooth on the upside surface of the rivet cap of anodal rivet (7) and negative pole rivet (8).

2. The cover plate device for the lithium battery according to claim 1, wherein a pressure relief explosion-proof hole (11) penetrating through the thickness direction of the cover plate body (1) is formed at a middle position in the length direction of the cover plate body (1), a pressure relief explosion-proof mechanism (12) is arranged on the pressure relief explosion-proof hole (11) and at a position corresponding to one side of the cover plate body (1) facing away from the insulating pad (2) in the use state, an explosion-proof mechanism installation cavity (111) is formed on the cover plate body (1) and around the pressure relief explosion-proof hole (11) in the circumferential direction, and the pressure relief explosion-proof mechanism (12) is fixedly connected with the explosion-proof mechanism installation cavity (111) in the state corresponding to the pressure relief explosion-proof hole (11).

3. The cap plate device for a lithium battery according to claim 2, wherein the pressure-releasing explosion-proof mechanism (12) includes an explosion-proof plate (121) and a protective film (122), an explosion-proof plate pressure-bearing chamber (1211) is formed at a central position of the explosion-proof plate (121), the explosion-proof plate pressure-bearing chamber (1211) has a hemispherical structure and is disposed at an upper position corresponding to the pressure-releasing explosion-proof hole (11), a peripheral edge portion of the explosion-proof plate (121) is welded to a chamber bottom wall of the explosion-proof mechanism mounting chamber (111), and the protective film (122) is disposed at an upper position corresponding to the explosion-proof plate (121) and a lower surface of the protective film (122) is attached to an upper-facing side surface of the cap plate body (1).

4. The cover plate device for a lithium battery as claimed in claim 3, wherein the explosion-proof sheet (121) is made of aluminum foil, and the protective film (122) is made of plastic and is in a transparent state.

5. The cap plate device for a lithium battery as claimed in claim 1, wherein a positive electrode plate insulating sleeve (31) is fixed by injection bonding at a position near the left end of the upper side surface of the cap plate body (1) and corresponding to a position below the positive electrode plate (3), and similarly, a negative electrode plate insulating sleeve (41) is fixed by injection bonding at a position near the right end of the upper side surface of the cap plate body (1) and corresponding to a position below the negative electrode plate (4).

6. The cover plate device for the lithium battery as claimed in claim 2, wherein the cover plate body (1) is provided with a liquid injection hole (13) at a position corresponding to the pressure relief explosion-proof hole (11) and the position between the positive plate (3), the liquid injection hole (13) penetrates through the thickness direction of the cover plate body (1) and the liquid injection hole (13) can be used for injecting electrolyte into the shell cavity of the lithium battery shell, and the insulating base plate (2) is provided with a liquid injection abdicating hole (21) at a position corresponding to the liquid injection hole (13).

7. The cover plate device for the lithium battery as claimed in claim 1, wherein the insulating base plate (2) is attached to the surface of the cover plate body (1) facing the lower side, a positioning protection box (22) is formed at the middle position of the insulating base plate (2) in the length direction, a plurality of explosion-proof vent holes (221) are formed in the bottom plate of the positioning protection box (22) and at the lower position corresponding to the pressure relief explosion-proof holes (11), a plurality of explosion-proof vent holes (222) are formed in the peripheral side plates of the positioning protection box (22), pin positioning plates (23) are respectively formed at the two ends of the insulating base plate (2) in the length direction, and the two pin positioning plates (23) are respectively used for positioning the anode pin (52) and the cathode pin (62).

8. The cap plate device for lithium battery according to claim 1, wherein at least one positive plate rivet hole (32) penetrating the thickness direction of the body is formed on the positive plate (3), a positive base plate riveting hole (511) is also arranged on the positive base plate (51) of the positive connecting piece (5) and at the position corresponding to the positive plate riveting hole (32), riveting holes are also arranged on the cover plate body (1), the insulating backing plate (2) and the positive plate insulating sleeve (31) corresponding to the positive plate riveting holes (32), the positive rivet (7) sequentially penetrates through the corresponding positive base plate riveting hole (511), the insulating base plate (2), the cover plate body (1), the positive plate insulating sleeve (31) and the positive plate riveting hole (32) from top to bottom, the positive connecting piece (5) and the positive plate (3) are connected and riveted together and realize the electrical conduction relation; similarly, the negative plate (4) is provided with at least one negative plate riveting hole (42) penetrating through the thickness direction of the body, a negative base plate riveting hole (611) is also arranged on the negative base plate (61) of the negative connecting piece (6) and at the position corresponding to the negative plate riveting hole (42), riveting holes are also arranged on the cover plate body (1), the insulating backing plate (2) and the negative plate insulating sleeve (41) at positions corresponding to the negative plate riveting holes (42), after the negative rivet (8) sequentially passes through the corresponding negative base plate riveting hole (611), the insulating base plate (2), the cover plate body (1), the negative plate insulating sleeve (41) and the negative plate riveting hole (42) from top to bottom, and connecting and riveting the negative electrode connecting piece (6) and the negative electrode plate (4) together to realize the electrical conduction relationship.

9. The cap plate device for a lithium battery as claimed in claim 5, wherein the cap plate body (1) is made of aluminum plate, and the insulating backing plate (2), the positive plate insulating sheath (31) and the negative plate insulating sheath (41) are made of polytetrafluoroethylene.

10. The cover plate device for a lithium battery according to claim 1, wherein the positive electrode connector (5) and the negative electrode connector (6) are of an integral structure, and the indented surfaces of the upper side surfaces of the rivet caps of the positive electrode rivet (7) and the negative electrode rivet (8) are of a grid-shaped rack structure surface.